Glossary

Phenylalanine

Glossary / Phenylalanine
Amino Acid

Phenylalanine — An essential aromatic amino acid (Phe, F) with a benzyl side chain, contributing to UV absorption at 257nm and used in spectrophotometric analysis.

Category
Amino Acid
Glossary Section
P

What Is Phenylalanine?

Phenylalanine (Phe, F) is an essential aromatic amino acid with a benzyl side chain (MW: 165.19 Da). It provides hydrophobic contacts in receptor-ligand binding pockets and is a key residue in the pharmacophore of many bioactive peptides including enkephalins (Phe4), substance P (Phe7-Phe8), and CCK.

Significance

  • Chymotrypsin substrate: Chymotrypsin cleaves after Phe, Trp, and Tyr, making aromatic residues determinants of proteolytic half-life
  • D-Phe: D-Phenylalanine is incorporated in ipamorelin, GHRP-6, and PT-141 for protease resistance and receptor selectivity
  • Non-natural analogs: 4-Fluoro-Phe, 4-Chloro-Phe, naphthylalanine (Nal) are common substitutions in SAR studies

Frequently Asked Questions

What is Phenylalanine?

An essential aromatic amino acid (Phe, F) with a benzyl side chain, contributing to UV absorption at 257nm and used in spectrophotometric analysis.

Why is Phenylalanine important in peptide research?

Phenylalanine is a fundamental concept in amino acid as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.

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